Metro Gold Line Eastside Extension Tunnels deemed UCA project of the year

摘要

Hailed as a model for America by U.S. Transportation Secretary Ray LaHood, the successfully delivered Metro Gold Line Eastside Extension (MGLEE) celebrated its grand opening Nov. 14,2009. The line extends the Los Angeles County Metropolitan Transportation Authority's (Metro) light rail system to the densely populated and continuously growing East Los Angeles communities. Much of the alignment consists of at-grade track, but the project also features a 2.7-km (1.7-mile) underground segment in cut-and-cover and twin-bored tunnel structures. For the first time, Metro specified, the use of pressure face tunnel boring machines (TBM) to advance the tunnels through soft ground. The tunnel design, construction management and construction methods adopted resulted in the successful completion of the tunnel segment with virtually no surface impact.